Sickle-cell anaemia - Complications of sickle cell anaemia

Sickle cell anaemia can cause serious complications.

The abnormal shaped blood cells can block blood vessels and prevent oxygen reaching parts of body, which can cause tissue and organ damage. These are described below.

Stroke

A stroke is one of the most serious complications of sickle cell anaemia. It can happen when the sickle cells block the flow of oxygen to the brain.

The main stroke symptoms can be remembered with the word FAST which stands for Face-Arms-Speech-Time.

• Face – may have dropped on one side, the person may be unable to smile or their mouth or eye may have drooped
• Arms – the person may not be able to lift one or both arms and keep them there due to arm weakness or numbness
• Speech – may be slurred or garbled, or the person may be unable to talk at all
• Time – dial 999 immediately if you see any of these signs or symptoms

Some people with sickle cell anaemia may experience a transient ischaemic attack (TIA), or ‘mini-stroke’. A TIA occurs when the supply of blood to the brain is temporarily interrupted.

Symptoms of a TIA are similar to those of a stroke, and last from a few minutes to a few hours before disappearing completely. However, a TIA shouldn't be ignored because it's a serious warning that there's a problem with the brain’s blood supply.

If you or your child has a TIA, contact your GP, local hospital or out-of-hours service immediately to arrange a specialist assessment.

Strokes can be treated by blood transfusions. Blood transfusions aren't effective for treating strokes in people who don't have sickle cell anaemia because the causes are usually different, such as a blood clot or burst artery.

Once the person’s condition has stabilised, it's usually recommended that they continue to have regular blood transfusions to reduce the risk of further strokes.

Acute chest syndrome

Acute chest syndrome is a life-threatening lung condition. The exact cause is unknown but it's thought that an infection in the lungs, which are already damaged by sickle cell anaemia, can cause problems with air circulating there.

The symptoms of acute chest syndrome include:

• high temperature (fever) of 38C (100.4F) or above
• chest pain
• cough 
• breathing difficulties
• more rapid breathing than normal

If you think your child has acute chest syndrome, dial 999 immediately to request an ambulance.

Acute chest syndrome requires emergency medical treatment with antibiotics, blood transfusions, oxygen and intravenous fluids (where liquids are pumped directly into your child’s veins to help rehydrate their body).

Splenic sequestration crisis

Splenic sequestration crisis (SSC) is a complication that can affect young children between six months and three years of age with sickle cell anaemia.

SSC occurs when the sickled red blood cells become trapped inside the spleen. This causes the spleen to swell and at the same time leads to a dangerous decrease in the number of red blood cells in the rest of the body.

Symptoms of SSC include:

• unusually pale skin
• feeling very tired
• shortness of breath
• irritability
• tachycardia (rapid heartbeat)
• abdominal pain, usually in the left side of your child’s abdomen
• swelling of the spleen (you should be able to check for this by gently touching the upper left side of your child’s abdomen, just underneath their rib cage)

If you think your child has SSC, contact your GP or a member of your child's care team immediately for advice. If this isn't possible, call your local out-of-hours service or NHS 111.

Some episodes of SSC are minor and resolve on their own without the need for treatment. However, more severe episodes will require a blood transfusion in hospital.

Vision problems

In some cases of sickle cell anaemia, blood vessels that lead to the eyes can get blocked by sickled cells, causing damage to the retina known as retinopathy. The retina is a light-sensitive layer of cells at the back of the eye that processes incoming light and sends signals to the brain.

Symptoms of retinopathy can include:

• floaters (coloured spots that ‘float’ in your field of vision)
• blurred vision
• vision blocked by patches or streaks
• reduced night vision
• sudden vision loss

Contact your sickle cell care team for advice if you or your child experience any deterioration in vision.

Retinopathy can be treated using laser surgery to repair damage to the blood vessels and retina. Eye examinations should be carried out at least once a year.

Pulmonary hypertension

Pulmonary hypertension is high blood pressure in the blood vessels that carry blood from the heart to the lungs. It's a common complication that affects more than half of all teenagers and adults with sickle cell anaemia.

Pulmonary hypertension is a serious medical condition because it damages the right-hand side of the heart, making the heart less efficient at pumping blood around the body and getting oxygen to the muscles. This leads to symptoms such as:

• shortness of breath 
• fatigue (tiredness)
• feeling faint or dizzy

If it's not treated, pulmonary hypertension can cause heart failure, where the heart struggles to pump enough blood around the body. This can be fatal.

Because of the risk of heart failure, your care team may recommend regular tests to check the blood pressure inside your blood vessels using an echocardiogram.

An echocardiogram is a type of ultrasound scan that can be used to check how well your heart is working. The procedure uses high-frequency sound waves to create an image of your heart. The image can be used to estimate the pressure inside your pulmonary arteries.

Treatment options for people with sickle cell anaemia who develop pulmonary hypertension include hydroxycarbamide and regular blood transfusions. These treatments aren't used in people with pulmonary hypertension who don't have sickle cell anaemia.

In some cases, medications designed to widen blood vessels and reduce blood pressure, such as iloprost and sildenafil, can be tried.

Read more about the treating pulmonary hypertension.

Kidney problems

The kidneys are designed to filter waste products out of the blood. However, because of the ‘stickiness’ of blood in people with sickle cell anaemia, the kidneys can become damaged over time. This can lead to a number of problems such as:

• having blood in your urine
• bedwetting
• high blood pressure (hypertension) – the kidneys play a role in regulating blood pressure

In the past, around one in three adults with sickle cell anaemia experienced end stage kidney disease (also known as kidney failure). This is where the kidneys lose most or all of their functioning abilities. However, recent advancements in treatment should improve these figures.

Treatment options for kidney failure include dialysis, where a machine is used to replicate the functions of the kidney or a kidney transplant.

Depression

Living with a condition as unpredictable as sickle cell anaemia can cause anxiety and stress, which often leads to depression.

Research has found around half of people living with sickle cell anaemia will experience depression at least once during their life.

It can be difficult to spot depression in children, particularly in teenagers, because they're often reluctant to talk about their feelings with their parents.

Signs your child may be depressed include:

• no longer showing interest or taking pleasure in activities they used to enjoy
• an inability to make or keep friends
• lack of energy
• problems sleeping or, alternatively, sleeping much more than usual
• changes in their diet, either eating much more or much less than usual
• a sudden worsening of behaviour, such as getting into trouble at school or frequent rule breaking at home
• a general lack of enjoyment in day-to-day life

If you're concerned that your child may be depressed, encourage them to talk about their feelings in a calm, non-judgemental way.

Mild to moderate depression in children and young people is often treated with talking therapies, such as cognitive behavioural therapy (CBT).

CBT is based on the principle that the way a person feels is partly dependent on the way they think about things. It teaches children and young people to behave in ways that challenge negative thoughts – for example, confronting feelings of hopelessness.

More severe depression is usually treated using a combination of talking therapies, such as CBT, and antidepressant medications, such as fluoxetine.